I've had my NEX-5 for about 6 weeks now, and i'm extremely happy about the purchase. I guess it all depends on what your skill level and expectations of the camera are, but I fit the target demographic for this camera perfectly - a p&s user that wanted more quality and full manual controls to grow into as my skills get better. It's a perfect bridge camera for me and I would assume many others just like myself.
The new v3 firmware has definitely made the camera more friendly to use, so a firmware upgrade will likely be the first thing you do to the camera. It takes great pictures (especially considering it's size), and the full HD video quality is better than my dedicated HD camcorder (I guess due to it's much larger sensor size). Full auto is nice if you're looking for point and shoot simplicity, put it into program auto if you need a little handholding while you learn the settings, or go into any of the other manual modes as you grow into the camera. All settings changes are reflected on the screen, so you can see in realtime the effect your adjustments will have on the picture before it's snapped. Plus plus in my book.
My co-workers are a bunch of bonafide camera nuts and were naturally curious about the NEX-5 after my purchase. I directed them to the review here and they asked me to bring it to the office for them to play with. A week later, two of them purchased the NEX-3 as a starter camera for their wives to get into the hobby.
I live in a city that has breathtaking architecture that is beautifully lit at night, so this was naturally my biggest draw to the NEX cameras - the handheld low light features cannot be beat. Me and a few colleagues went roaming about the city one night with our cameras (Nikon D90, Canon 50d and 550d, and my NEX-5). They struggled with on the fly low light shots and had to revert to tripods to get decent results at slow shutter speeds. I on the other hand was able to snap nice low light shots by hand. It also seemed that the NEX had better noise performance at higher ISO's than their considerably more expensive cameras. One disadvantage I had was the lack of phase change focusing, so I had to rely on manual focus assist in the lowest of lighting conditions (not much contrast for a contrast-based focusing system in near darkness). This was not usually a problem as the autofocus would usually lock onto a light source and happily snap away.
The only regret I do have is that the camera shop was sold out of the dual lens kits when I picked mine up, so I grabbed the kit with the 18-55 zoom. Now I wish I had that 16mm pancake as well
Accessories are sparse for this camera due to my location, so I can't comment on any of that. I will however be investing in more lenses as they become available, and definitely some type of case.